1. Field of the Invention
This invention relates to an image forming apparatus, such as mainly a copier and a printer and so on, comprising a latent image holder and a cleaning means integral with each other to adopt the so-called process kit.
2. Description of the Prior Art
The image forming apparatus, such as copier periodically carries out exchange of a latent image holder (usually drum-like-shaped), supply of toner and developer, discard of waste toner, and exchange and maintenance of other several parts. In the conventional apparatus, above exchange and maintenance of these parts have been carried out by a service man of professional knowledge who goes to the site each time, which has been very troublesome and increased a maintenance and administrative cost.
Under the above circumstances, construction such that the latent image holder and a cleaning means, or a toner hopper and a developing means, are coupled in unit so that each one unit is exchanged in batch, has been put into practical use. Hence, a user can exchange simply by himself the main components necessary for periodical maintenance, whereby exchange and maintenance by a service man is not necessary, and it is possible that a user prepares toner of various colors filled in different units and uses them properly.
In the above-mentioned construction, parts included in the same unit, for example, the latent image holder and cleaning means are not always equal in a life time, so that when one of them causes trouble or breakage for some reason, the other, even still usable, has to be discarded. Hence, such construction is rather uneconomical and may cause a high maintenance cost in comparison with conventional image forming apparatus.
On the other hand, the apparatus of the latent image holder and cleaning means coupled in unit has a great fear that, when the unit is mounted or dismounted to or from the apparatus body, the latent image holder may be injured at the surface. In detail, the conventional apparatus is provided at the body with a peel-off device for peeling off a recording paper from the surface of the latent image holder during the operation for image forming, whereby the peel-off device slidably contacts with the surface of the latent image holder axially thereof each time the latent image holder is exchanged. Hence, a flaw is liable to be created on the surface of the latent image holder axially thereof, thereby causing deterioration of the quality of the image forming on the recording paper. Also, it is required to exactly maintain the relative positional relation between the latent image holder and the peel-off device, but there is a great fear that the positional relation between both the parts is out of order as the latent image holder often is mounted or dismounted to or from the body. When the latent image holder and peel-off device have therebetween the inaccurate positional relation, the recording paper is peeled off not-reliably from the latent image holder, thereby causing paper jamming and breakage thereby on the latent image holder.